Muzzle-loading rifles are generally reproductions of rifles of former times. They are usually reproductions which are true to the original; however, the increase made in the U.S.A. and Canada in the sport of hunting, which might use muzzle-loading guns, has caused a new type of such guns to come about, which might not have any link to the old guns except for the manner of loading and the ammunition. Such guns are the conversion into muzzle-loading of breech-loading models that are usually known by the term Bolt Action, and as such, they usually have a cocking and closing mechanism with straight-line motion in the rear zone of the barrel. For this purpose, the barrel proves to be relatively long and it has an opening on top or on the side for the access to the so-called wick holder and the insertion of the trigger cap for igniting the load in the barrel.
However, the access to the wick holder is narrow and awkward, which limits the freedom of maintenance and polishing of the parts involved as well, which are fundamental actions when black powder, which is necessary for muzzle-loading guns, is used.
Beyond its appearance in terms of aesthetics, the breech-loading rifles do have cocking mechanisms and systems for closing the barrel in the receiver which are completely different from those of the muzzle-loading rifles.